System units for treatment of aggregate material

ABSTRACT

An aggregate storing and classifying mechanism for production of asphalt in plants, comprising a body ( 2 ) having plurality of circular sections ( 6 ) arranged in a manner of substantially surrounding the body ( 2 ) for storing aggregate material comprising different gradation levels plurality of foot means ( 1 ) holding said body ( 2 ); corridor means ( 7 ) and channel means ( 15 ) arranged tree branch-like manner in the body ( 2 ) for distributing and storing the aggregate in the body ( 2 ) as homogenously; plurality of discharge mouths ( 4 ) and discharge covers ( 8 ) for discharging the aggregate material from the body ( 2 ) and feeding the aggregate material to conveyors placed under the body ( 2 ) through plurality of discharging axis.

TECHNICAL FIELD

The present invention relates to production method and mechanism for theproduction of bituminous hot mix (asphalt) in plants where aggregate andmicro granulated dust particles obtained from ballast material are usedas raw material and collected within a closed system. In this system,aggregate materials are crushed and separated through screensconsidering the requirement for their relative particle sizes and gradesand deposited. Later aggregates are either transferred into the asphaltplant for continuous feeding of the system or taken directly fordischarge.

BACKGROUND ART

In order for better understanding of present invention, terms anddefinitions characteristic to this technical field are explained below:

-   Aggregate: Main raw material used in asphalt production, obtained    through crushing of hard stone particles.-   Bitumen: raw material obtained from petroleum, used to attach    aggregates to each other.-   Crusher Plant: Plant for crushing and sieving hard stone particles.-   Asphalt Plant: Plant for asphalt production.-   Asphalt: Material obtained from mixing of aggregate with bitumen,    used especially for paving of roads and open spaces.-   Gradation: Relative size of a stone particle in a graded series.-   Ballast: Stone particles with 25-65 mm in size, they are crushed in    primary crusher after extracted from stone quarry to be separated    from other foreign particles.

Asphalt is obtained through several steps which involve the mixing ofhot bitumen with specified sized of aggregates collected togetheraccording to their sizes and heated in a controlled manner.

In FIG. 1, hard stones used in asphalt production are shown. They areobtained through dynamiting stone quarries, mines or river beads andtransferred into crusher unit. This material usually contains soil andlarge, coarse stone particles which are crushed with various crushingelements such as jaw crusher, impact crusher, hammer crusher etc. at twostages known as primary crushing and secondary crushing. This is shownin FIG. 2.

In order to produce aggregate, first soil material inside the crushedstone particles are roughly eliminated through by-pass system latercoarse stone particles go through crushing and sieving stages to produceaggregates at required sizes in crushing units which are arranged inhorizontal fashion.

As it is seen in FIG. 2, crushing procedure is carried out at twosequential orders called primary crushing stage and secondary crushingstage. Transport and conveyance between these two stages are made withconveyors.

Large stone particles are almost reduced less than 150 mm in size inprimary crushing whereas a further reduction in size which is almostless than 25 mm is get through secondary crushing.

Crushed stones (aggregates) are classified according to their sizes bypassing through screens at various sizes (FIG. 2) and these classifiedaggregates (for example classified between 0-4 mm, 4-7 mm, 7-12 mm and12-19 mm) are stored at open areas as shown in FIG. 3 without allowingthem to mix with each other. Each category of classified aggregates isthen transferred to cold aggregate bunkers to be used as raw materialfor asphalt production. This is shown in FIG. 4.

Aggregates are transferred into conveyors (FIG. 4) via passing throughfeeders placed under bunkers and discharged into drying oven whereaggregates are advanced inside the oven by a rotating motion and driedwith the help of hot air and heated inner surface of dryer oven as aresult of vaporization of water vapor inside aggregates. Temperatureinside dryer is raised up to 160 C. Drying ovens are generally heatedwith burners which consumes fuel either in liquid or in gas forms. (FIG.4).

Burned gases from drying oven are thrown out usually with an exhaustpipe after they have been initially treated with a high capacity dustretaining filter placed above the plant's exhaust system in order toprevent;

-   -   1. environmental pollution which is caused as a result of mixing        and spreading of micro granulated dust particles inside        aggregate and burned air inside dryer oven with water vapor and        exhaust gases during emptying from pipe,    -   2. escape of dust particles, which are important raw material        for good quality asphalt production and to store them

Dust particles are retained in cyclones of this filter system to be usedas filler material. As shown in FIG. 4, this application is started tobe widely used except some plant types.

Filler material collected in cyclone units are transferred into fillersilo through the use of spiral conveyor (FIG. 4).

Aggregates heated and dried in dryer oven are transferred into asphaltplant through vertical elevator (FIG. 4). As it is seen in the figure,hot aggregates are passed through with multi-layered screen unit forfurther screening, classified according to their sizes and dischargedinto hot aggregate bunker.

Aggregates required for asphalt production at certain quantity and sizesare weighed automatically and transferred into mixer.

On the other side, bitumen which will also be used in asphalt productionare automatically weighed in bitumen weighbridge and added intoaggregate content inside the mixer.

Now, aggregates and bitumen which come together inside the mixer arethoroughly mixed during a definite time interval to obtain a homogenousbituminous hot mixture (FIG. 4).

Mixture obtained through this process are either directly dischargedover carrying vehicle or stored in ready asphalt bunkers before carryingfor use.

DISADVANTAGES OF THE PRESENT STATUS OF THE ART

Crusher Unit Settlement Area

Any crusher unit which will feed an average size asphalt plant having aproduction capacity of 2.000 ton per day should produce and storeapproximately 20.000 tons of aggregate only to meet the need for 10days.

Since the transfer of 20.000 tons of aggregate from stone quarry tocrusher plant as well as the storage of aggregates may give rise tocertain difficulties, crusher plants are usually established at openareas with close vicinity to stone quarries.

Crushing and sieving units of a crusher plant which are operated basedon the current state of technical knowledge are constructed beingintegrated in a horizontal settlement order which one unit follows theother and material transfer between units are carried out with conveyorsin the same plane (FIG. 2).

Storage Areas

As it may be comprehended from above explanations that the structuralintegrity which conforms to current state of technical knowledge andasphalt production processes initially require crushing of entireaggregates at all gradation levels and storage for further usage.

The main units of an asphalt plant are structurally large and wide interms of mass and volume and they require a certain period of time toattain the required process conditions such as operation temperature.Therefore, an uninterrupted operation is what the manufacturer looks forafter plant has been operated. On the other hand, a continuous plantoperation depends on one important factor that is the presence ofrequired quantity and sizes of aggregates at a proper time duringoperation in order to feed the plant continuously.

A continuous plant operation is however quite not practical yetunfeasible in terms of a coordination between plant and crusher unitproviding a sustained material feed where at least in existing operatingsystems at which units are arranged horizontally according to open areasystem. Furthermore, complex structure of equipments, need for wideareas, high cost of investment and operation and full stop of wholesystem when a fault occurs make continuous operation impractical in theview of asphalt manufacturers.

Therefore, asphalt manufacturers tend to operate asphalt plant andcrusher unit separately and store required amount of aggregate at allgradation levels prior to asphalt production. This high amount ofaggregates is deposited at large storage areas until they are going tobe used.

Another factor which makes storage inevitable is that the amount ofaggregates obtained after crushing, sieving and classification do notmeet the real aggregate amount required for asphalt production.Therefore, the amount of aggregates produced in a crusher unit areplanned in order to meet the possible highest aggregate requirement.Also the uncontrollable distribution rates of different sized ofaggregates renders the production of excess amount of aggregatesnecessary also the storage of finished aggregates in large and closedareas prior to asphalt production brings additional investment costs anddifficult.

Aggregates which are classified in the best gradation level 0-4 mm.constitute about 50% of total aggregate requirement for asphaltproduction. These aggregates which are usually stored at open areasuncovered are easily gone away due to wind effect. These size ofaggregates which are easily blown (under 1 mm.) are the most importantaggregate class for quality asphalt production. In case of underproduction of this aggregate class where production does not meet therequirement, supply through outside means is both troublesome anddifficult.

To take necessary precautions to get rid of the wind effect such asbeing covered by a canvas sheet is not always possible in fact it ispreferable not to cover aggregates to get benefit from heating effect ofsunshine for drying aggregates. However, storage of aggregates at openareas may give rise to numerous unwanted effects which in turn spoil thequality of asphalt produced.

The Effect of Wind

During the determination of the area at which crusher unit will besettled, factors such as direction of dominating wind at the area shouldbe considered as it will adversely effect both worker's health andenvironment due to spreading of dust particles around with the windeffect. A light wind in the area is always preferable. When no windblows there, heavy dust arising during operation sinks over the unitsrendering crusher unit almost unworkable. Another negative factor whichis due to wind effect is that when the area is exposed to heavy wind,dust particles are spread around and they are no longer usable as fillermaterial which is required as an important input for asphalt production.

Some crusher plants use water pulverization method to wet aggregates asa means of subsiding dust in certain cases but the quality of asphaltproduced using wet aggregates is affected unfavorably.

The Effect of Mixing with Foreign Particles

Maintenance the ground and surroundings of aggregate stock areas is notalways easy. Aggregates usually mix with other foreign substances orfine stock aggregates are not prevented from mixing with soil substancesof storage areas. Also, aggregates from different gradation levels mixeach other.

The Effect of Outside Weather

Aggregates are get wet due to the effect of outside weather conditionssuch as rain and snow. When aggregates contact with water and moisture,they usually tend to absorb water and keep it inside since they have alarge surface area to contact with thus leading a decrease in thequality of asphalt produced because water oxidizes metal moleculesinside the aggregates and asphalt produced from oxidized aggregates ispoor in quality.

The Effect of Dust Particles Sticking to Aggregates

When aggregates are get wet, they become more prone to surrounded bydust particles which, during transport and carrying of aggregates withconveyors, are thoroughly adhere to the surface of aggregate and form anouter shell which do not come off easily even during the drying stage ofaggregates inside the dryer and stay at the surface of large aggregateparticles. This situation prevents homogenous mixing of aggregates withbitumen during asphalt production because this outer shell later driesforming a film layer over aggregates thus preventing it from making ahomogenous mixture with bitumen so the result is poor quality asphaltformation.

Dusting Effect During Transfer, Loading and Discharge of Aggregates

While aggregates are transferred from crusher unit either to storageareas or to asphalt plant, they are loaded and discharged several timescausing a significant amount of dust to form. Lorries are generally usedto transfer aggregates from one place to another at short distances andduring transfer to cover aggregates with a canvas sheet is not a routineapplication. As a result, dusting during loading and discharge ofaggregates has the same effect with dusting which forms at crushing unitand it only contributes the situation.

Effect of Environment

Noise which result from transfer, screening, loading and dischargeactivities of aggregate together with energy-emission have inverselyeffect the environment and people working in the area. Also, themaintenance costs for the equipments used for this purpose bothincreases the overall investment and also reduces the productivity.

Effect of Energy Wasted During Drying of Aggregates

In order to achieve a homogenous mixture of aggregate and bitumen whichis at the required quality during asphalt production, the whole mass ofaggregates should be dried at dryer oven which is heated up to 160 C.Aggregates stored and kept at open areas are get wet and thus contain asignificant amount of water inside which should be first evaporated toeffectively dry aggregates. Heat energy required for heating of wet andhumidified aggregates constitutes an important item with respect toenergy and investment costs of the procedure.

Another consequence of high energy consumption during heating and dryingof humidified aggregates is the increased exhaust gases emission valueswhich is the result of using high amount of fuel at drying stage.Another undesired effect of high water content of aggregates is thewater vapor which forms as a result of hot air released through dryeroven's chimney. Since the water vapor contained inside the hot gasesreleased from chimney gets a muddy appearance together with dust on dusttrapping filters and clogs on the meshes thus decreasing filter'spermeability and work performance. A clogged filter bag keeps air fansto absorb air properly. Under these circumstances, the amount of oxygenrequired for efficient burning of fuel used in dryer burner is notsupplied sufficiently as a result dryer capacity is decreased andunburned gases diffuse atmosphere.

On the other hand, when aggregates are crushed, heat energy is formeddue to friction between aggregate surfaces and this energy enables asignificant amount of water vapor to evaporate. However, due totemperature loss of aggregate material deposited at places open toatmosphere, humidification re-occurs and energy created during frictionis wasted.

The Effect of Utilizing Micro Granulated Dust Particles in Production

Dust is formed in two ways in an asphalt plant:

-   -   1—as a result of crushing, screening and transfer processes of        aggregates in crusher unit, after loading and discharge of        aggregates at storage areas and at the end of drying, screening        and carrying processes of aggregates in asphalt plant,    -   2—micro granulated particles separated from aggregate itself.

Micro granulated dust particles are not only a fundamental element forthe quality of asphalt produced but also an important raw material forother industrial sectors such as pharmaceutical, cosmetics, chemical anddye industry. If granulated dust particles can be obtained insubstantial amounts after above described processes, they can be bothused in asphalt plant as quality enhancer and as raw material for otherindustrial sectors. However, for some of the abovementioned reasons suchas the localization of crusher units in wide areas, their open systemoperation, wide storage places which make the control of dust formationdifficult, a great portion of dust formed is also get lost. In thiscase, some industrial sectors encounter with the loss of an importantraw material and meet this requirement by applying some specialproduction processes which are high in cost or import it. So, theindustrial contribution of this material is underestimated. Thissituation is further increasing the importance of collecting microgranulated dust particles without letting them spread to theenvironment. Nevertheless, to collect even a tiny amount of particlesbefore they dispense through the surrounding in conventional open,horizontal displacement areas where usually equipment and machinery aredispersed is difficult and requires the implementation of a highlycomplex dust absorption system which is more expensive than the plantitself. Although the social awareness and enforcements for environmentalpollution have been raised, the alternatives to the conventional systemare not practical for most of the companies.

The Effect on the Quantity of Bitumen and Asphalt Quality

The quantity of aggregates that should be contained in asphalt mixtureand the proportion of bitumen are two critical factors which aredetermined by technical calculations and based on laboratorial tests andexperiments according to the purpose of using asphalt, its strength andthe type of aggregate. The less proportion or high proportion ofaggregate in asphalt mixture directly affects the quality of asphalt.The amount of bitumen less than the required prevents aggregates tostick well each other on the other hand amount which is higher than therequired lessens the strength and usage life of asphalt and causesdeformation in a short period. Therefore, the correct proportion ofbitumen inside asphalt mixture should be carefully calculated,controlled and maintained at optimum levels for quality asphaltproduction.

However, in conventional open, horizontal displacement plant areas wheresoil and foreign substances easily mixed with aggregate can not beeffectively removed, the amount of bitumen which is higher than therequired amount is used because soil and foreign substances form a thinlayer around aggregate so that bitumen absorption by aggregates is madedifficult. Improved bitumen absorption is only accomplished when theamount of bitumen is higher than the required amount. In this case, toomuch bitumen decreases the quality of asphalt. On the other hand,bitumen being a by-product of petroleum is the high cost entry withinexpense items so the increase in its amount is undesirable with respectto production costs.

The Effect on Asphalt Production Cost

As it has been explained in above paragraphs, despite all theseunfavorable conditions and regardless of the type and number of crushingand screening stages as well as the processes applied in conventionalopen, horizontal displacement plant areas which currently prevail,control and prevention of unwanted mixing of aggregates with soil andforeign substances can not be accomplished. Since the asphalt isproduced from aggregates which can not be separated from impurities andchanged into ballast form and low quality asphalt is obtained at ahigher cost.

This invention which has been explained in the following section, offersa new way to eliminate or at least minimize all the disadvantages of thepresent system by providing an industrially applicable, improved systemand procedure for producing high quality asphalt at a lower cost.

DESCRIPTION OF THE INVENTION

The object of the invention is to provide a method for using soil-freeaggregates in asphalt production by producing ballast material from hardstones later processing it to eliminate others.

Another object of the invention is to provide a system to eliminateunnecessary investment costs required for the collection of microgranulated dust particles which appear during asphalt production orcrushing processes.

It is still another object of the invention is to provide means for thestorage of ballast materials before they are brought to final gradation.By this way, we can;

-   -   reduce the storage costs because we can eliminate the necessary        production requirement for producing the highest amount of        aggregates that will be needed for asphalt production,    -   remove the harmful effect of oxidation of metal molecules caused        by humidification of aggregates,    -   reduce the requirement for storage areas,    -   reduce the harmful environmental effect by preventing the        dissemination of micro granulated dust particles,    -   create more healthy working environment for people at plant,    -   remove the dusting effect which forms during transfer, loading        and discharge of aggregates,    -   stop the noise which results during transfer, screening,        discharge and loading procedures of aggregates and terminate the        harmful effects of energy emitted during operation of equipment        in above procedures,    -   reduce the repair and maintenance costs of equipments used in        above procedures and prevent the reasons which can hinder        production and reduce the production capacity,    -   prevent the mixing of aggregates with foreign particles such as        soil and other impurities.

Another object of the invention is to provide a system to make use ofmicro granulated dust particles as raw material in other industrialapplications.

Another object of the invention is to prevent micro granulated dustparticles from sticking on the surface of aggregates forming anuninterrupted film layer which later on inhibits a homogenous mixtureformation between aggregates and bitumen.

Another object of the invention is to reduce the energy requirement andconsequently decrease investment costs.

Another object of the invention is to prevent using too much fuelconsequently decrease chimney gas emission values.

Another object of the invention is to prevent water vapor released withhot air from exhaust pipe to adhere on the surface of dust retardingfilters and consequently remove any unwanted effect which will hinderthe filter's function.

Another object of the invention is to prevent the decrease in dryer'scapacity and diffusion of unburned gases to the atmosphere.

Another object of the invention is to decrease the energy requirement ofdryer oven by preventing the humidification of aggregates which havebeen already heated and dried with the effect of heat energy forming asa result of friction between aggregate surfaces.

Another object of the invention is to make possible the use of microgranulated dust particles as raw material for other industrialapplications in such as pharmaceutical, cosmetics dye and chemicalindustries.

Another object of the invention is to increase the quality of asphalt byproviding a better homogenization of aggregate and bitumen.

Another object of the invention is to decrease cost and increase asphaltquality through optimum utilization of bitumen.

Another object of the invention is to provide a continuous feeding ofasphalt plant by storing aggregates at different gradations in the sameclosed system.

Another object of the invention is to provide the exact quantity ofaggregates required by production just in time owing to the advantage ofcontinuous feeding of asphalt plant which provides the adjustment ofcrusher's revolution speed.

Another object of the invention is to provide a mechanism for feeding ofmore than one asphalt plant accomplishing plenty numbers of transfersand feedings of aggregates each at different axis under the newmechanism.

Another object of the invention is, when necessary, to provide amechanism for direct discharge of aggregates into the vehiclesaccomplishing plenty numbers of transfers and feedings of aggregateseach at different axis under the new mechanism.

Another object of the invention is to provide a mechanism for thestorage of aggregates at more than one gradation category and to alterstorage capacities according to requirement of asphalt plant.

Another object of the invention is to provide a mechanism for thestorage and collection of dust particles through direct absorption fromplant units owing to a completely covered operation after secondarycrushing stage.

The abovementioned mechanism constructed within the context of presentinvention is generally consist of a frame body within which aggregatematerial from secondary crusher is contained in circular compartmentsand foot which support the body.

Screens are positioned at the upper site of the area where aggregatesare entered into the mechanism hence aggregates at the requiredgradation category are deposited inside the body. Direction flow ofaggregates toward respective circular compartments according to theirgradation level is accomplished with directing channels.

Homogenous distribution and storage of aggregates at various placeswithin the body through circular compartments and easy passage ofaggregates with directing channels between compartments areaccomplished. Horizontal passage corridors between circular compartmentsprovide a means for the utilization of circular compartments as onecomplete compartment.

The lower ends of circular compartments are designed in conical form fora convenient release of aggregates during asphalt production.

EXPLANATION OF ILLUSTRATIONS

In order to comprehend the present invention together with its wholeauxiliary elements, following illustrations should be evaluated as acomplementary part of the invention.

FIG. 1 illustrates a stone quarry settlement order as a part of presentpractice.

FIG. 2 illustrates crusher plant settlement order arranged according topresent settlement criteria.

FIG. 3 illustrates aggregate storage areas arranged according to presentsettlement criteria.

FIG. 4 illustrates asphalt plant settlement order arranged according topresent settlement criteria.

FIG. 5 illustrates crusher plant settlement order arranged according topresent invention.

FIG. 6 illustrates asphalt plant settlement order arranged according topresent invention.

FIG. 7 Perspective illustration of a sectional structure of aggregateclassification and storing sections according to present invention.

FIG. 8 illustrates a cross sectional view of aggregate classificationand storing sections for indicating how distinctly graded aggregates areclassified and distributed at different ranges.

FIG. 9 illustrates schematic view of how aggregate discharge covers arealigned and oriented with conical structure of aggregate classificationand storing sections designed at lower part according to the presentinvention.

FIG. 10 illustrates a perspective view of aggregate classification andstoring sections arranged according to present invention.

FIG. 11 illustrates structure of aggregate filling covers arrangedaccording to present invention where aggregates coming from screens areoriented towards the body of the mechanism via directing channels.

FIG. 12 illustrates schematically of how more than one aggregatedischarge covers are aligned at more than one axis arranged according topresent invention.

REFERENCE NUMBERS OF PARTS GIVEN AT EACH ILLUSTRATION

-   -   1 Foot    -   2 Body    -   3 Screen    -   4 Discharge mouths    -   Directing part    -   6 Circular sections (segments)    -   7 Corridors    -   8 Covers    -   9 Lower body surface    -   10 Outer surface of body    -   11 Piston    -   12 Paddle box    -   13 Dust suction pipes    -   14 Filling mouths    -   15 Channels    -   16 Flow mouth

DETAILED EXPLANATION OF INVENTION

This mechanism constructed within the context of present inventionfunctions in a general scheme of the processes outlined below:

Quarry material which generally contains soil and large and coarse stoneparticles is firstly crushed in primary crusher and treated to eliminateits foreign particles by by-pass system. Crushed material is carriedinto sieving unit via conveyors, screens through them and classifiedaccording to their sizes. Ballast material with 25-65 mm particles sizesare separated from others in sieving unit and deposited in open storageareas for further use in asphalt production. Other classified group ofmaterials are carried via conveyors to open areas and utilized as highquality filler material which is required for asphalt production.

Therefore, ballast material deposited at open areas before they arecrushed to bring them into required particle sizes are being subject toharmful effects of storage at open places.

By using the mechanism constructed within the context of our presentinvention, ballast material deposited at open storage areas for asphaltproduction are transferred into the cold aggregate bunkers (silos).

Ballast materials which have been removed from impurities are crushed insecondary crusher and are directly transferred via conveyors and closedform vertical elevators into the screens located on the constructedmechanism.

The crushing revolution of the secondary crusher as well as the speed,flow rate and crushing sizes of ballast material can be adjustedaccording to the gradation level of aggregates required in asphaltproduction. As a consequence, only the sufficient amount of aggregatescan be obtained as required by asphalt production which is subject tovariable gradation levels throughout the production.

The required and obtained amounts of aggregates can be balanced throughthis mechanism which removes the need for making a production planningto determine the exact required amount for asphalt production.

The aggregate material discharging from the secondary crusher is fedinto a vertical elevator having closed from structure through conveyorbelts and then the aggregate material is sieved in proportion togradation rates required by asphalt production by vibrating screens (3)located on the constructed mechanism and then classified. The vibratingscreens, like the body (2) and the elevator, have completely closed-formstructure and are in association with a filter system for sucking dustvolume caused by crushing the aggregate.

Screen (3) is located at the top of the body (2) where aggregates areentered into the body (2) thus after sieving, aggregate material canfreely fall down and fill the store body (2).

Aggregates are directed towards their respective circular sectionsinside the store body based on their gradation rates with the help ofdirecting parts.

There are plurality of circular sections placed inside and in a mannerof surrounding the storing body (2) for the homogenous storage ofdifferent category aggregates [K1 (4-7 mm), K3 (7-12 mm), K4 (12-19 mm)]by dispersing them through sections.

As it is seen in FIGS. 7 and 8, there are channels (15) and corridors(7) between circular sections (6). The channels (15) and corridors (7)are disposed as tree branch-like manner in the body (2) and they provideflow of aggregates in the direction of discharge mouths (4) withoutdisturbing their homogenization during this flow. They can also providethe utilization of all of the plurality of circular sections (6) in theform of a single section when it is required i.e. requirement withregard to volume of aggregate and the number of gradation.

The base segment of the constructed mechanism is given a conicalconstruction for free fall of deposited and classified aggregates toenable them to go towards the discharge mouths (4).

In FIG. 10, aggregate classification and storing sections according topresent invention are shown. Sections comprise one main body (2) withinwhich aggregates are deposited and a foot (1) component which supportbody and connect it to the ground. The certain features of inventedmechanism for instance the number of foot (1) and storing sections (6),the capacity of body, the number of different gradations and means ofaccess between sections can be altered as to feed the aggregaterequirement of the asphalt plant or modifications on the presentmechanism can be added afterwards.

In FIG. 10, aggregates are sieved passing through screens (3) positionedat the top of the new closed system mechanism in order to be classifiedaccording their gradation rates.

Thus sieved and classified aggregates are sent to the sections (6)arranged in a circular manner within the body (2) by directing parts (5)which direct the flow of aggregates.

After the aggregates have been entered to the main body (2) via fillingmouths (14) that are arranged on the upper side of the body (2), theyare directed into the sections (6) as free fall under the influence ofgravity, as it is seen in FIGS. 11 and 8.

Since the capacities of each storing sections is varied in order toproperly arrange the deposition of more than one graded series ofaggregates at various quantities, the number of sections (6) which willbe constructed within the body (2) is determined to match eachcategories of aggregates. These storing sections (7), corridors (15) andchannels also render a balanced distribution and storage of aggregateswithin the body. Moreover, it is also being possible to chance thenumber of gradations and storage capacities by giving a new form tostoring sections in order to accommodate with the changes in aggregaterequirement over time. One more advantage of circular sections withinthe body is that a full body is used to control the center of gravity.

Within the context of present invention, the body has been constructedin view of operational conveniences in both production and assembly ofthe invented mechanism.

Storing sections (6) which are in circular form have been symmetricallyarranged within the body (2) but upon the requirement, more than onecircular section can be united by constructing horizontal passages (7)(15) to form a unique single storing section. This has been shown inFIG. 9.

Aggregate material are freely discharged from the top and allowed tostore circular sections within the body with its free fall. Channels andcorridors between sections are branched to provide a homogenousdistribution within the sections. This has also been shown in FIGS. 11and 8. These channels provide material flow from one section to theother at different levels.

Accordingly, when the material level is increased inside the silo,aggregate freely move between these channels thus making it possible tomaintain a steady material level without disturbing the homogenization.Heavy aggregate particles are kept from falling at the bottom.

Aggregates which are continuously sieved at top screens fill thesections by passing through channels and corridors and keeping theirfilling level and homogenous formation. When they reach at dischargemouth (4), discharge covers (8) are opened up easily with weight ofaggregates allowing aggregates to discharge homogenously andcontinuously for feeding the conveyors placed under the body (2) forconveying thereof to the asphalt plant.

This mechanism works under completely closed system to allow for theclassification, storage and continuous feeding of asphalt plant and dustforming through above processes is absorbed and collected with the helpof a paddle box (12) as well as dust absorbing pipes (13). With thismethod, dust is not allowed to spread to environment instead collectedwithout undergoing much loss of quantity and the requirement for microgranulated dust particles also called filler material in asphaltproduction is met.

According to FIG. 12, the lower sides of each storing section (6) weregiven a conical shape to allow for the collected aggregates to freelyflow down to the conveying vehicle. Under each storing sections, thereare discharge mouths (4) separately designed for each category ofgradations such as K1 (0-4 mm), K2(4-7 mm), K3(7-12 mm), K4(12-19 mm).

For each category of gradations, more than one discharge mouth on morethan one axis can be operated and the number of discharge mouths can bedetermined according to the aggregate feeding requirement of asphaltplant.

The shape and dimensions of the lower surfaces of the body are alsodetermined depending on the number and dimensions of discharge mouths.

The body's outer edges (10) which have been shaped in the form of a coneare connected with the lower surface (9) and the body itself (2) byignoring the main body structure when it seems necessary (FIG. 10).

As it is seen in FIG. 12, the cover openings of discharge mouths (4)(the gap which forms when the cover (8) is opened to release aggregates)of each storing sections which belong to each category of gradations andsituated at the lower surface of the body (9) in the direction ofdifferent axis can be adjusted as to discharge the exact quantity ofaggregates. Discharge mouth cover (8) openings (10) can be adjusted withhydraulic pistons (11) connected to a control system which operateseither mechanically or electronically depending on request.

As it is seen in FIG. 12, it can be accomplished through dischargemouths (4) situated in duplicate on the same axis to feed more than oneasphalt plant placed either in parallel or in different directions on(AA) and (BB) axis. This also enables a more flexible usage ofproduction capacity or only a 50% reduction in capacity of instead ofcompletely shut-down production when there is a breakdown in one plantbecause the other plant can be operated at 50% capacity by means ofsupplementary feeding on different axis.

For continuous feeding of asphalt plant, discharge of material can beaccomplished through discharge mouths (4) which directly pour thematerial onto the conveyor unit or conveyor is brought to suitable sizesas to enable it to discharge aggregates into a carrying vehicle placedunder the body. Height of conveyor from the vehicle and distance betweenconveyor feet are accordingly arranged to accomplish direct loading ofcarrying vehicle which comes between conveyor feet.

Another aspect of the present invention is to have the method steps forproviding classification and storage of aggregates and comprising thefollowing sequences;

-   -   crushing of ballast material in secondary crusher which is        covered with the paddle box (12) and connected to a filter        system for the absorption of dust,    -   controlled crushing through which aggregate flow rate, flow        speed, gradations and the amount of each gradation are managed        with modifications made on the revolution speed of the secondary        crusher,    -   transferring of aggregate material to the closed vertical        elevator which is connected to filter system for the absorption        of dust,    -   transferring of aggregates in a vertical position with the        vertical elevator to screens (3) of the mechanism,    -   sieving of aggregate material with screens (3) which are covered        with the paddle box and connected to a filter system for the        absorption of dust,    -   directing the flow of aggregates towards inside the mechanism        using directing parts and delivering aggregates into storing        sections with respect to their gradations,    -   storing of more than one size (gradation) of aggregates in a        completely closed system,    -   storing of more than one size (gradation) of aggregates by        changing (either increasing or decreasing) their quantity when        it is required,    -   absorbing and storing of dust particles which form after        secondary crushing without causing them to spread to the        environment,    -   direct discharging or discharging through feeding system (mule        system) of deposited materials from discharge mouths (4) either        manually or by automatic control,    -   placing of horizontal conveyor bands which can make aggregate        transfer in more than one axis under the mechanism,    -   placing plurality of discharge mouths (4) along with the same        axis for enabling feeding of two separate asphalt plants        situated at two different directions.

1. An aggregate storing and classifying mechanism for production ofasphalt in plants, comprising a body (2), a screen (3) arranged to theupper side of the body, plurality of foot means (1) for holding the body(2), plurality of discharge mouths (4) and discharge covers (8) fordischarging the aggregate material from the body (2) and feeding theaggregate material to conveyors placed under the body (2) throughplurality of discharging axis, a paddle box (12), and the aggregatestoring and classifying mechanism being in association with an elevatorto convey the aggregate material provided by a secondary crusher to thescreen (3), characterized in that, in a closed-form structure, the body(2) comprises plurality of sections (6) arranged in the body (2) forstoring aggregate material comprising different gradation levels;corridor means (7) and channel means (15) arranged in the body (2) fordistributing the aggregate in the body (2) as homogenously.
 2. A closedform aggregate storing and classifying mechanism according to any one ofthe preceding claims, characterized in that the elevator is in closedform as the aggregate string and classifying mechanism.
 3. A closed formaggregate storing and classifying mechanism according to claim 2,characterized in that the elevator is a vertical elevator and being inassociation with a filter system for sucking dust volume of theelevator.
 4. A closed-form aggregate storing and classifying mechanismaccording to any one of the preceding claims, characterized in that thesecondary crusher is covered by the paddle box (12).
 5. A closed-formaggregate storing and classifying mechanism according to any one of thepreceding claims, characterized in that the screen (3) is a vibratingscreen and the upper side thereof is covered.
 6. A closed-form aggregatestoring and classifying mechanism according to any one of the precedingclaims, characterized in that pistons (11) operable by mechanically orelectronically, are provided for opening and closing the dischargecovers (8).
 7. A closed-form aggregate storing and classifying mechanismaccording to any one of the preceding claims, characterized in that apaddle box (12) and dust suction pipes (13) are provided for sucking thedust originated in the screen (3), in the crusher and in the body.
 8. Aclosed-form aggregate storing and classifying mechanism according toclaim 1, characterized in that the corridor means (7) and the channelmeans (15) are provided horizontally, so that said plurality of sections(6) are united to form a single storing section.
 9. A method for storingand classifying of aggregate according to any one of the precedingclaims, comprising the following steps of: crushing of ballast materialin the crusher which is covered with the paddle box (12) and connectedto a filter system for the absorption of dust, controlled crushingthrough which aggregate flow rate, flow speed, gradations and the amountof each gradation are managed with modifications made on the revolutionspeed of the secondary crusher, transferring of aggregate material tothe closed vertical elevator which is connected to filter system for theabsorption of dust, transferring of aggregates in a vertical positionwith the vertical elevator to screens (3) of the mechanism, sieving ofaggregate material with screens (3) which are covered with the paddlebox and connected to a filter system for the absorption of dust,directing the flow of aggregates towards inside the mechanism usingdirecting parts and delivering aggregates into storing sections withrespect to their gradations, storing of more than one size (gradation)of aggregates in a completely closed system, storing of more than onesize (gradation) of aggregates by changing (either increasing ordecreasing) their quantity when it is required, absorbing and storing ofdust particles which form after secondary crushing without causing themto spread to the environment, direct discharging or discharging throughfeeding system (mule system) of deposited materials from dischargemouths (4) either manually or by automatic control, placing ofhorizontal conveyor brands which can make aggregate transfer in morethan one axis under the mechanism, placing plurality of discharge mouths(4) along with the same axis for enabling feeding of two separateasphalt plants situated at two different directions.